The present invention relates to cooling arrangement and, more particularly to a cooling arrangement for semiconductor devices for removing or dissipating heat generated, for example, semiconductor integrated circuit chips of a large-sized electronic computer and a method of making a sintered composite material for the cooling arrangements.
With the advent of large-sized electronic computers having a high processing speed, circuit chips having large scale integrated semiconductor elements have developed and, in order to make the electric wiring which interconnects the integrated circuit chips as short as possible, a number of methods of techniques have been proposed for mounting a large number of integrated circuit chips in a micropackage.
Cooling devices have been proposed in, for example, U.S. Pat. Nos. 3,993,123, 4,263,965, 4,770,242, 4,498,530 and Japanese Patent laid-open nos. 23463/83, 57-103337, 59-144153 and 61-32819.
Additionally, Japanese patent laid-open no. 60-126853 proposes a cooling device for a semiconductor device which provides for a superior cooling performance and which employs a resilient construction permitting assembly erro and heat deformation to be absorbed vertically and transversely.
In proposed cooling devices or systems employing a plurality of fins, the fins are disposed at a relatively small spacing from each other, with the device being fashioned of a material such as SiC or AlN which is considerably difficult to machine. Consequently, there are a number of disadvantages of the proposed constructions, namely, the poor processing of the material, required manufacturing techniques, etc., so that the cooling system is not comparable to other cooling systems from a point of view of production costs even though the proposed constructions may exhibit superior cooling capabilities.
Moreover, in a semiconductor electronic circuit for which a high-speed processing is required such as, for example, a large-sized electronic computer, the circuit output level differs in accordance with operating temperatures of the circuit, so that it is necessary that the temperatures of the LSI chips be maintained within a predetermined temperature range.
Furthermore, a large number of LSI chips mounted on a micropackage are not always used in such a manner that the quantity of heat generated is the same with respect to each of the chips by virtue of the logic design of the high speed electronic computer. On the other hand, if the fins of the proposed cooling devices are formed so as to have the same shape, number, and material, it follows that the fins fitted together have the same cooling performance. Consequently, in conventional cooling systems or devices, in order to maintain the temperature of the LSI chips having different generated quantities of heat within a predetermined temperature range, it is necessary to alter the shape and number of the fins for each LSI chip thereby raising a serious problem with regard to manufacturing costs when considering industrial mass production.